Clench tube for safeguarding scaffold workers



F. A. VOIGT' 2,172,094

CLENCH TUBE FOR SAFEGUARDING SCAFFOLD WORKERS I Sept.-5, 1939.

Filed Sept. 27, 1938 Patented Sept. 5, 1939 UNITED STATES CLENCH TUBEFOR SAFEGUARDING SCAFFOLD WORKERS Frederick A. Voigt, Park Ridge, Ill.

Application September 27, 1938, Serial No. 231,927

Claims.

In general the present invention relates to metallic clench-tubes forsafe-guarding scaffold workmen against injury in the event that theyshould inadvertently fall from the scafiold or 5 the scaffold shouldaccidentally drop as the result of failure of the scaffold sustainingropes or the rope hooks. More particularly the invention relates to thattype of clench-tube which is designed for attachment to a safety belt,is adapted to extend loosely around the usual workmans hand or guiderope so as not to interfere with the wearers scaffold activities, andhas at the upper and lower ends thereof diagonally opposite V-shapednotches which are adapted when the tube becomes inverted as the resultof dropping or falling of the wearer to have the contiguous portions ofthe guide rope become wedged therein in such manner that the tubebecomes locked to the rope and serves to hold the wearer until he canright himself and slide down the guide rope to safety.

As evidenced by United States Letters Patent No. 1,127,832 granted to meFebruary 9, 1915, it has heretofore been the practice to form aclenchtube of this type of a pair of complemental semicylindricalsections, one of which embodies at its upper end an apertured lug for aring on the safety belt and has in its lower end one of the guide ropereceiving notches and the other of which has the other notch in itsupper end and is connected to the one section by a latch at one side anda hinge at the other side so that it may be swung into an openpositionin connection with application of the tube to the guide rope and removalof the tube from the rope. A clench-tube of the aforementioned characterhas proved in practice to be defective or faulty because its strength islimited or restricted to the strength of the latch and the hinge. Ifeither or both of these should fracture or break as the result of theterrific shock or strain to which they are subjected when the tube isbrought into its operative inverted position in response to falling ordropping of the wearer, the tube would not fulfill its intended purpose.

One object of the present invention is to provide a clench-tube of thetype under consideration which is an improvement upon, and eliminatesthe defects of the tube of the aforementioned patent by reason of thefact that it comprises instead of a pair of complemental semicylindricalsections a one-piece three-quarters round section which has bothV-shaped notches for rope wedging purposes formed therein and is closedat the open side by way of a hinged previously designed clench-tubes byreason of the 1 fact that the one-piece three-quarters round sectionembodies on the portions thereof that are disposed diametricallyopposite to the notches novel 'means whereby when the tube is invertedinto its operative position as the result of falling or dropping of thewearer, the portions of the guide rope that are adjacent to the notchesare deflected in a quick manner into wedged relation with the notchesand there is hence less sliding of the tube with respect to the ropeupon inversion thereof.

A further object of the invention. is to provide a clench tube which isgenerally of new and improved construction and includes spring meanswhereby the door'is urged into its closed position and thuspreventsdislodgment of the guide rope from the tube in the event ofbreakage or failure of the latch.

Other objects of the invention and the various advantages and.characteristics of the present clench-tube will be apparent from aconsideration of the following detailed description,

The invention consists in the several novel features which arehereinafter set forth and are more particularly defined by claims at theconclusion hereof.

In the drawing which accompanies and forms a part of this specificationor disclosure and in which like numerals of reference denotecorresponding parts throughout the several views:

Figure 1 is a perspective view of a safety belt having applied thereto aclench-tube embodying the invention;

Figure 2 is a similar perspective view showing the tube in its invertedor operative position and in clenched relation with a workmans hand orguide rope; r I

Figure 3 is a side view of the clench-tube showing the construction anddesign of the door for closing the open side of the one-piecethreequarters round sectionj."

Figure 4 is a front vi ew of the tube;

Figure 5 is a vertical-or longitudinal sectional view taken on the line5 5 of Figure 4 and showing in detail" the rounded lugs which are notchit disposed opposite to the V-shaped notches and serve quickly todeflectthe contiguous portions of the guide rope into the notches in connectionwith inversion of the tube;

Figure 6 is a horizontal or transverse sectional View taken on the line6-6 of Figure 3; and

Figure 7 is a top view of the tube.

The clench-tube which is shown in the drawing constitutes the preferredembodiment of the invention. It is designed to be carried by a safetybelt b around the waist of a scafiold workmanand is adapted inconjunction with a hand or guide rope r to act as a safety devicewhereby the wearer of the tube is prevented from being injured in theevent that he should fall inadvertently or otherwise from the scaffold,or the scaffold should drop accidentally as the result of failure ofscaffold sustaining ropes or the rope hooks. The belt I) embodies abuckle h for releasably and adjustably securing its ends together. It isadapted to be worn in a tight manner around the waist and embodies atone side thereof a D-ring U The, latter is suitably held againsthorizontal sliding movement with respect to the adjacent portion of thebelt and constitutes anchor means for the tube. The tube comprises asthe main parts thereof an elongated three-quarters round section 8 and adoor 9.

The section 8 is in the form of a one-piece casting and is adaptednormally to be suspended from the safety belt b. It is adapted when inits. operative position loosely to encircle the guide rope r so as notto impair or hamper the scaffold activities of the wearer of the tube.At its upper end the tube section 8 embodies an integral longitudinallyextending apertured lug it! which, as shown in Figlhes 1 and 2, isadapted to interengage the D-ring b on the safety belt I). Th aperturein the lug I9 is of greater diameter than the thickness of the ring withthe result that the tube is free to swing upwardly from a normalsuspended position into an inverted position, as shown in Figure 2, inresponse to falling or dropping of the wearer of the tube. A, v-shapednotch H is formed in the upper end of the tube sece tion 8 directlyopposite to the apertured lug l0 and an inverted V-shaped notch I2 isformed in the lower end of the tube section directly be neath the lug I9and diagonally opposite to the When the tube is inverted as a result offalling or dropping of the wearer of the tube, as hereinbeforedescribed, the portions of the guide rope T which are adjacent orcontiguous to the notches become wedged in the notches, as shown inFigure; 2, with the result that the tube becomes clenched or clamped tothe guide rope, stops the fall or dropping of the tube wearer, andservesto hold the latter suspended from the guide rope until he canright himself and slide down the rope to safety. The portions of thetube equal in width to the diameter of the rope with the result that thesection 8 may be readily brought into encircling relation with the ropein connection with placement of the tube in its operative position andalso readily withdrawn '28 and a lower internal rounded lug 29.

from the rope in connection with release of the tube.

The door 9 serves to close the side opening in the section 8 and thus tocomplete the tube. This door is substantially the same in length as thesection 8 and is connected to the latter by a hinge connection [4. Theupper and lower ends of the door are shaped conformably to the upper andlower ends of the section 8. The

. hinge connection I4 is located at one side of the door 9 and arearranged in lapped relation with the lugs l5, as shown in Figure 3. Thepivot pin H extends through aligned holes in the lugs l5 and i6 and hasheads H3 at its ends whereby'it is held against longitudinaldisplacement. The specific hinge connection shown permits the door 9 tobe swung outwardly into an open position. In such position of the door,the. section 9 may be placed in encircling relation with the guide roper or withdrawn from the guide rope.

Upper and lower stop ears l9 are formed on the outer distal margin ofthe door and are adapted when the door is in its closed position to abutagainst the contiguous side margin of the section 8 and prevent inwardmovement of the door. A coil spring 29 on the pivot pin i1 urges thedoor 9 into its closed position. This spring is mounted on the centralportion of the pin between the lugs l5 and has the ends thereof arrangedone in abutment with the section 8 and the other in abutment with thedoor 9. By employing the spring there is no likelihood of the doorswinging into its Open. position during inversion or operation of theclench tube. In order releasably to lock the door in its closedposition, a latch 2| is provided. This latch comprises a latch dog 22which is slidably mounted in a horizontally elongated housing 23 inthecentral portion of the outer face of the door 9. The end of the dogwhich is remote from the hinge connection I4 is adapted when the dog isshifted away from the hinge connection to enter a socket equipped lug 24on the section 8. The dog is urged toward the. lug 24 by way of acompression spring 25 which surrounds the dog and is disposed in thehousing 23. A pin 26 extends through a slot 21 in the housing and isattached to the dog 22. This pin embodies a head which is adapted to beengaged by the finger in connection with retraction of the latch dog..Whenthe dog is retracted by shifting it towards the hinge connection andthus disengaging the end from the socket equipped lug 24 release of thelatch is effected and the door 9 is free to be swung open in connectionwith application of the tube to the guide rope or removal of the tubefrom the rope.

In order quickly to deflect the guide rope 1' into the V-shaped notchesH and 12 upon inversion of the clench-tube as the result of falling ordropping of the tube wearer, the section 8 is provided with an upperinternal rounded lug The upper lug is disposed beneath the apertured lugill and in opposed relation with the V-shaped notch I I. It issubstantially hemispherical and is positioned substantially in alignmentwith the mouth or upper portion of the notch H. The lug 29 is the samein size and shape as the lug 28 and is located in opposed relation withthe inverted V-shaped notch 12. It is positioned in substantialalignment with the lower or mouth portion of the notch l2, and is formedas an integral part of the section 8. The lug 29 is also formed as anintegral part of the tube section 8, When the clench-tube is inverted asthe result of falling or dropping of the tube wearer there is a tendencyfor the rope to swing back and forth. When the portions of the ropewhich are contiguous to the lugs 28 and 29 strike such lugs they bounceor are deflected quickly away from the latter into the notches II and12. Because of the action of the lugs the guide rope is quicklydeflected into the notches dur ing inversion of the tube and the tubehence is locked to the rope in a quick manner and without sliding to anyappreciable extent on the rope. By obtaining a quick locking of the tubeto the rope the fall of the tube wearer is materially restricted andhence the wearer and the section 8 are subjected to but a minimum amountof shock.

In using the safety device which is composed of the safety belt and theclench tube, the belt is first buckled around the wearers waist. Thedoor 9 is then unlatched and swung into its open position, andthereafter the section 8 is brought into encircling relation with theguide rope. After the section 8 is brought into such relation with theguide rope, the door is closed and locked in place by propermanipulation of the latch dog 22. In the event that the tube wearershould fall from the scaffold or the scaffold should drop because offailure of the scaffold sustaining ropes or the rope hooks, the tubebecomes inverted and during inversion of the tube and the portions ofthe guide rope which are disposed adjacent to the lugs 28 and 29 bounceor are deflected away from such lugs into wedged relation with thenotches H and I2, and the tube thus becomes locked to the guide rope andprevents further falling of the tube wearer.

The herein described clench-tube effectively and efliciently fulfillsits intended purpose. It may be manufactured at a comparatively low andreasonable cost, and in addition, is especially strong due to the factthat the rope receiving V- shaped notches H and I2 are formed in asingle section and no shock or strain is imparted either to the hingeconnection 14 or the latch 2| during swinging or inversion of the tubeinto its operative position. When the tube is in its normal position itslides freely with respect to the guide rope and hence the tube wearersactivities on the scaffold are not restricted or hampered.

The invention is not to be understood as restricted to the details setforth, since these may be modified within the scope of the appendedclaims, without departing from the spirit and scope of the invention.

Having thus described the invention, what I claim as new and desire tosecure by Letters Patent is:

1. As a new article cf manufacture, a clenchtube adapted to encircle aguide rope and to be carried loosely by, and serve as a safety devicefor, a scaffold workman, and comprising a onepiece elongatedtransversely rounded section having at one side thereof a full lengthopening of substantially the same width as the rope is in diameter forpermitting the section to be brought into encircling relation with therope and removed from the rope after use thereof, and also having aV-shaped notch in one end thereof and adjacent one side of the openingand a v-shaped notch at its other end adjacent to the other side of saidopening for receiving the contiguous portions of the rope upon inversionof the tube due to fall of the workman, and a door shapedcorrespondingly to, and serving to close, the side opening in thesection.

2. As a new article of manufacture, a clenchtube adapted to encircle aguide rope and to be carried loosely by, and serve as a safety devicefor, a scaffold Workman, and comprising a onepiece elongatedtransversely rounded section having at one side thereof a full lengthopening of substantially the same width as the rope is in diameter forpermitting the section to be brought into encircling relation with therope and removed from the rope after use thereof, and also having aV-shaped notch in one end thereof and adjacent one side of the openingand a V-shaped notch at its other end adjacent to the other side of saidopening for receiving the contiguous portions of the rope upon inversionof the tube due to fall of the workman, a door for closing the sideopening in the section hinged to one side margin of said section andhaving a latch between it and the other side margin of said section, andspring means for urging the door into its closed position.

3. As a new article of manufacture, a safety device for a scaffoldworkman comprising a clench-tube adapted to encircle a guide rope and tobe carried loosely by the workman and having a pair of diagonallyopposite V-shaped notches at its ends for receiving the contiguousportions of the rope upon inversion of the tube due to fall of theworkman, and means at the ends of the tube and in opposed relation withthe notches for deflecting said contiguous portions of the rope into thenotches upon inversion of the tube.

4. As a new article of manufacture, a safety device for a scaffoldworkman comprising a clench-tube adapted to encircle a guide rope and tobe carried loosely by the workman and having a pair of diagonallyopposite V-shaped notches at its ends for receiving the contiguousportions of the rope upon inversion of the tube due to fall of theworkman, and a pair of rounded lugs in the ends of the tube in opposedrelation with the notches for deflecting said contiguous portions of therope into the notches upon inversion of the tube.

5. As a new article of manufacture, a clenchtube adapted to encircle aguide rope and to be carried loosely by, and serve as a safety devicefor a scaffold workman, and comprising a onepiece elongatedsubstantially three-quarters round section having a pair of diagonallyopposite V-shaped notches at its ends for receiving the contiguousportions of the rope upon inversion of the tube due to falling of theworkman and also having at its ends a pair of internal integralsubstantially hemispherical lugs opposite the notches for deflectingsaid contiguous portions of the rope into said notches in connectionwith inversion of the tube, and releasable means for closing the openside of the section.

FREDERICK A. VOIGT.

